Guiding apparatus for a work head



Jan. 15, 1963 G. 2. GOWIN 3,073,197

1 GUIDING APPARATUS FOR A WORK HEAD Filed Dec. 5, 1958 3 Sheets-Sheet 1Fig. I. 35

IN V EN TOR. GRovER Z. Gowllv ATTORNEY Jan. 15, 1963 G. 2. GOWIN3,073,197

GUIDING APPARATUS FOR A WORK HEAD Filed Dec. 5, 1958 3 Sheets$h eet 2 In IIGVENTOR. F GROV -R Z. Gowuv Fig AZ/WC/ 5M ATTORNEY Jan. 15, 1963 G.2. GOWIN 3,073,197

GUIDING APPARATUS FOR A WORK HEAD Filed Dec. 5, 1958 3 Sheets-Sheet 3INVENTOR. GROVER Z. Gow/Iv ATTORNEY movement thereover.

United States Patent 3,073,197 GUIDING APPARATUS FOR A WORK HEAD GroverZ. Gowin, Tunnel Hill, Ga., assignor to Singer- Cobble, Inc.,Chattanooga, Tenn., a corporation of Delaware Filed Dec. 5, 1958, Ser.No. 778,475 4 Claims. (Cl. 83368) This invention relates to a selvagetrimming apparatus for pile fabrics and particularly to a means forcontrolling the posltion of a selvage trimming element laterally of apile fabric to maintain the same in trimming relation to the pile edgeas the fabric is moved past the trimming element.

It is an object of this invention to provide a selvage trimmingapparatus for a pile fabric which is sensitive and automaticallyresponsive to the wandering of the pile edge as the fabric is moved pastthe trimming element for the purpose of guiding the tirmming elementalong and closely adjacent to the pile edge. Further objects of thisinvention are to provide such an apparatus which is economical,eflicient, reliable and durable.

In accordance with the above objects, the present invention comprises aselvage trimming apparatus having a sensing device adapted to engage apile edge and, through the friction generated between the pile-engagingelement and the moving pile, to bias an actuator pivotally in oppositionto a further bias whereby, when the pile edge moves toward and away fromthe pile-engaging element, the friction bias is correspondinglyincreased or decreased to move the actuator in a manner to adjust theposition of the trimming element to maintain the same in proper relationto the pile edge. By virtue of the opposed biases, the engagement of thepile-engaging element can be light, thereby permitting the same tooperate directly against the pile edge.

Further objects and advantages of the invention will be apparent fromthe following description taken in conjunction with the drawings,wherein:

FIG. 1 is a top plan view, at an angle of 45 to the horizontal, of theinvention operating to trim selvage from the edges of a pile fabric andwith the guide finger in neutral position;

FIG. 2 is a view similar to FIG. 1, disclosing the guide finger inalternate extreme positions;

FIG. 3 is a view taken along the lines 33 of FIG. 1;

FIG. 4 is a view taken along the lines 44 of FIG. 1;

FIG. 5 is an enlarged top plan view of the guide finger in alternateextreme positions;

FIG. 6 is a view taken along the lines 6-6 of FIG. 5.

Referring to the drawings now in more detail, a pile fabric 10, such asa carpet, having pile 11 and a selvage 12 is fed in the direction of thearrow over rolls 13, the ends of which are supported in bearings 14 onthe frame 15.

Also supported on the frame 15 and disposed transversely of thedirection of fabric feed are a pair of upstanding parallel plate membersforming tracks 20. These tracks 20 may be spaced apart by a longitudinalplate 21. Mounted to travel in either direction on the tracks 20transversely or laterally of the fabric is a carriage 22 for supportinga work head 23.

In the drawings, the work head 23 comprises a rotary cutter blade 24mounted on a shaft 25 which is driven by an electrical motor 26. Themotor 26 is fixed to the top of an inverted U-shapedcarriage housing 27which fits down over and envelops the tracks 20 for longitudinalSupported transversely between the walls of the housing 27 for freerolling movement over the tracks 20 are a pair of upper rollers 28.Lower rollers 29 may be provided to assist in retaining the carriagehousing 27 on the tracks 20, particularly when the earriage 22 ismounted at an angle, as disclosed in FIG. 3. Depending from the top wallof the carriage housing 27 between the upper rollers 28 is a block 30provided with a threaded opening 31 for receiving a long screw shaft 32extending parallel between the tracks 20 and adapted to be rotated ineither direction in order to drive the carriage 22 laterally toward andaway from the fabric 10. The screw shaft 32 is driven by means of areversible motor 33 through lower pulley 34, belt 35, upper pulley 36and reduction gear box 37.

When the cutter blade 24 is applied to a carpet having a foam rubberbacking, water 40 is applied to the blade 24 from a reservoir 41 througha Wick 42 located in the end of an outlet pipe 43, supported by an arm44 from the carriage 22, in order to dispel heat generated by therotation of the blade against the backing.

Attached to one wall of the carriage housing 27 is a bracket 47 forsupporting the guide frame 48 as a unitary part of the carriage 22. Theguide frame 48 comprises a switch bar 49 substantially parallel to thedirection in which the fabric is fed for supporting at either endthereof an electrical switch 50 and 51. The switches 50 and 51 areconnected through separate circuits 52 and 53 to a reversible motor 33.When the switch 50 is actuated, the motor 33 is adapted to rotate thescrew shaft 32 in such a direction as to drive the carriage 22 towardthe fabric 10. When switch 51 is actuated, the motor 33 will reverse therotation of the screw 32 to drive the carriage 22 away from the fabric10.

Mounted in the guide frame 48 to pivot about an axis substantiallyperpendicular to the plane of the fabric 10 is a post 55 carrying aguide arm 56 extending substantially at right angles to the post in thedirection of the fabric. The free end of the guide arm 56 is bentdownwards slightly at an angle between 10 to 20 degrees to form a guidefinger 57 extending laterally from the guide arm 56 in the direction offabric feed. The outer edge of the finger 57 is substantially straightover a short portion of its length and forms an angle slightly greaterthan 90 with the guide arm 56. The free end of the finger is arcuate andthe heel portion of the finger which joins the guide arm 56 and normallyabuts against the edge of the pile 11 is also arcuate to provide asubstantially rolling contact surface which slid-ably and frictionallyengages the pile 11 as the fabric 10 moves in the direction of thefinger 57. A contact bar 58 is also fixed to the post 55 transversely ofthe finger 57 and substantially coextensive with the switch supportingbar 49. Contact studs 59 and 60 are mounted at opposite ends of thecontact bar 58 for respective engagement with the contact finger 61 onswitch 50 and the contact finger 62 on switch 51 when that particularend of the contact bar is pivoted toward its respective switch. When thecontact bar 58 is substantially parallel to the switch bar 49 asdisclosed in FIG. 1, no contact is effected between the respective studsand fingers, so that neither switch 50 nor 51 is actuated to energizethe motor 33. Consequently, the screw shaft 32 is not rotated and thecarriage 22 remains stationary.

However, when the guide arm 56 is pivoted in the direction opposite thedirection of fabric feed as disclosed by the solid line positions ofFIGS. 2 and 5, the contact stud 59 will engage and depress the contactfinger 61 to actuate the switch 50 and energize the motor 33 to rotatethe screw shaft 32 in a direction which will cause the carriage 22 tomove toward the fabric 10. When the guide arm 56 is pivoted to itsextreme dashed line position in FIGS. 2 and 5, the carriage 22 is movedin the opposite direction away from the fabric because the con tact stud59 is disengaged from its finger 61 to open the switch 50, and thecontact stud 60 engages the contact finger 62 to close the switch 51.

- 64 is mounted toereate a counterclockwise moment about the axis ofthepost 55 when the contact bar 58 is at an angle of at least 35 to thehorizontal. The guide arm 56 is also located and the fabric 10 is fed inplanes forming the same angle with the horizontal. FIG. 3 disclosesthese elements mounted at an angle of Substantially 45 to thehorizontal.

The lateral position of the guide frame 48 with respect to the carriage22 may be adjusted .by means of the collar 65 which is fixed to thebracket 47 .and is threaded to receive an adjustable screw .66 manuallyoperated to laterally move the guide frame 48 in either direction in.small increments.

A tension member 67 may be provided for adjusting the elevation oftheguide arm 56 and guide finger 57 normal to :the plane of the fabric 10.

The operation .of the invention will now .be described asit is appliedto the accurate trimming of selvage from the edges of a pile fabric 10,even though the edges of the pile may be irregular or the fabric isinadvertently laterally shifted from time to time.

As-best disclosed in the drawings, the frame 15, the fabric rolls 1 3,'and the tracks are so disposed that fabric 10 is fed upward in thedirection of the arrow at an angle of approximately 45 from thehorizontal. The carriage 22 is mounted and moved along thetracks 20until the cutter blade 24 will cut the selvage 12 along the edge ofthepile 11. The screw 66 is then turned in the collar 65.to move theguideframe 48 until the guide finger 57 will abut against the side of thepile 11 with sufiicient pressure that the movement of the pile fabric 10at a constant velocity will develop sufficient friction with the edge ofthe guide finger 57 to overcome the effect of the weight 64 andmaintain-the contact bar 58 in a neutral position substantially parallelto the switch bar 49. Thus, neither of the switches 50 or 51 willbeactuated so long as the fabric 10 is moving in a longitudinal directionnormal to the axis of the cutter shaft* and there are substantially noirregularities on the edge of the pile 11.

If the edge of the pile 11 moves-laterally away from the guide ,finger,57 to reduce or eliminate the frictional contact between the finger 57and the edge of the pile 11,

the Weight-'64 will cause the guide arm 56 to pivot downward and-thecontact bar .58 to pivot against and actuate the switch 50 to .move thecarriage 22 toward the fabric 110 so that the cutter blade. 24'and theguide finger 57 will againabut against the edge of the pile 11' for anormal operation, If thefabric 1i shifts laterally toward the guidefinger or theedgeof the pile 11 bows outwardly, the increasedfrictionbetween the upwardly moving pile and the guide finger 57 willovercomethe effect of the weight '64 to .move theguide finger 57 upward,pivoting the contact bar 53 to. actuate the upper switch 51 to move thecarriage 22 away-from the fabric 10 so that the cutter blade 24.. willnot cut into the pile 11. The movement of the carriage 22 awayfrom thefabric will also reduce the friction between the guide finger 57 andtheedge ofthe pile 11 so that the guide arm 56 will resume its normalbalanced position.

The sensitivity and responsiveness of the apparatus which will determinethe accuracy and tolerance of the selvagetrimming operation will becontrolledby the spacing of the guide arm 56 relative to the cuttershaft 25, the spacing. of the contact studs. 59 and 60 relative to theirrespective contact fingers 61 and 62, the sensitivity of the switches 50and 51 and the reversible motor 33, the pitch of the threads andthe'speed of rotation of the screw shaft In order to trim theselvagefrom both lateral edges of a pile fabric such as carpeting, themirror-image of the above described apparatus is located on the otherside of the fabric. Also, if it is more convenient for the manufacturerto finish carpets by feeding the fabric downward, the apparatus may beadapted to operate equally effectively by locating the guide frame 48 onthe opposite side of the carriage 22 so that the guide finger 56 will belocated above and precede the cutter blade 24. The cutter blade may belaterally adjusted so that it may cut along the selvage to leave aborder or cut off a certain amount of pile in order to reduce theoverall Width of the carpet.

It can be readily understood that this type of guiding apparatus may beadapted for use with any type of Work head other than a cutter blade,such as a marking head for stamping the name of the manufacturer atuniform intervals along the bottom edge of the carpet.

This apparatus has been successfully employed in .automatically trimmingselvage from pile carpeting formed by either weaving or tufting, and hasconsistently produced a tolerance of one-sixteenth of an inch over anygiven length.

It will be apparent to those skilled in the art that various changes maybe made in the invention, without departing from the spirit and scopethereof, and therefore the invention is not limited by that which isshown in the drawings and described in the specification, but only asindi cated in the appended claims. 1

What is claimed is:

l. A selvage trimming apparatus for a pile fabric comprising means forfeeding the pile fabric in a longitudinal direction, a carriage, meansfor mounting said carriage for rectilinear movement along a line normalto a longitudinal edge of the pile fabric and carriage actuating meansfor moving said carriage in both directions along said line, a cutterblade mounted on said carriage and adapted to trim the selvage along 'aline longitudinally of the pile fabric, means on said carriage foractuating said cutter blade, and means for controlling the operation ofsaid carriage actuating means to maintain said cutter blade closelyadjacent to the pile edge comprising a guide arm, means for pivotallymounting said guide arm on said carriage for movement about a pivot axisin a plane normal to a plane defined by the pile fabric, first andsecond electricaljswitches mounted on said carriage, means on said guidearm for selectively closing said switches upon pivotal movement of saidguide arm in opposite directions from a neutral position in which bothof said switches are open, means electrically connecting said switcheswith said carriage actuating means for actuating the same to drive saidcarriage toward the pile fabric upon closing said first switch and todrive said carriage away from the pile fabric upon closing said secondswitch, a guide finger on said guide arm for overlying the selvage infront of said cutter blade and for frictionally engaging said pile edgeas the pile is moved past said guide finger, said frictional engagementbetween said pile edge and said guidefinger producing'a force componentin the direction defined by the fabric feedand acting upon the guidefinger to bias said guide arm pivotally in the direction to close saidsecond switch, and means for pivotally biasing said guide arm in thedirection to close said first switch, whereby said biases are opposedand, when balanced, said guide arm is disposed in the neutral positionand, when unbalanced, said guide is pivotally moved to close therespective one of said switches.

24A selvage trimming apparatus in accordance with claim 1 in which saidmeans for pivotally biasing said guide arm in the direction to closesaid first switch comprises a weight.

3. A selvage trimming apparatus in accordance with claim 2 in which saidmeans for feeding the pile fabric in a longitudinal direction acts tofeed said pile fabric at an acute angle to the horizontal.

4. A selvage trimming apparatus for a pile fabric comprising means forfeeding the pile fabric in a longitudinal direction, a carriage, meansfor mounting said carriage for rectilinear movement along a line normalto a longitudinal edge of the pile fabric and means including areversible electric motor for moving said carriage in both directionsalong said line, a cutter blade mounted on said carriage and adapted totrim the selvage along a line longitudinally of the pile fabric, meanson said carriage for actuating said cutter blade, and means forcontrolling the actuation of said motor to maintain said cutter bladeclosely adjacent to the pile edge comprising a guide arm, means forpivotally mounting said guide arm on said carriage for movement about apivot axis in a plane normal to a plane defined by the pile fabric,first and second electrical switches mounted on said carriage, means onsaid guide arm for selectively closing said switches upon pivotalmovement of said guide arm in opposite directions from a neutralposition in which both of said switches are open, means electricallyconnecting said switches with said motor for energizing the same todrive said carriage toward the pile fabric upon closing said firstswitch and to drive said carriage away from the pile fabric upon closingsaid second switch, a guide finger on said guide arm for overlying theselvage in front of said cutter blade and for frictionally engaging saidpile edge as the pile is moved past said guide finger, said frictionalengagement between said pile edge and said guide finger producing aforce component in the direction defined by the fabric feed and actingupon the guide finger to bias said guide arm pivotally in the directionto close said second switch, and means for pivotally biasing said guidearm in the direction to close said first switch, whereby said biases areopposed and, when balanced, said guide arm is disposed in the neutralposition and, when unbalanced, said guide is pivotally moved to closethe respective one of said switches.

References Cited in the file of this patent UNITED STATES PATENTS1,133,297 Lewis Mar. 30, 1915 1,468,396 Putt Sept. 18, 1923 2,210,925Hill Aug. 13, 1940 2,589,204 Parsons Mar. 11, 1952 2,747,666 Brooks May29, 1956 2,910,122 Anderson Oct. 27, 1959 3,036,483 Porter May 29, 1962FOREIGN PATENTS 285,213 Germany Dec. 31, 1913

4. A SELVAGE TRIMMING APPARATUS FOR A PILE FABRIC COMPRISING MEANS FORFEEDING THE PILE FABRIC IN A LONGITUDINAL DIRECTION, A CARRIAGE, MEANSFOR MOUNTING SAID CARRIAGE FOR RECTILINEAR MOVEMENT ALONG A LINE NORMALTO A LONGITUDINAL EDGE OF THE PILE FABRIC AND MEANS INCLUDING AREVERSIBLE ELECTRIC MOTOR FOR MOVING SAID CARRIAGE IN BOTH DIRECTIONSALONG SAID LINE, A CUTTER BLADE MOUNTED ON SAID CARRIAGE AND ADAPTED TOTRIM THE SELVAGE ALONG A LINE LONGITUDINALLY OF THE PILE FRABIC, MEANSON SAID CARRIAGE FOR ACTUATING SAID CUTTER BLADE, AND MEANS FORCONTROLLING THE ACTUATION OF SAID MOTOR TO MAINTAIN SAID CUTTER BLADECLOSELY ADJACENT TO THE PILE EDGE COMPRISING A GUIDE ARM, MEANS FORPIVOTALLY MOUNTING SAID GUIDE ARM ON SAID CARRIAGE FOR MOVEMENT ABOUT APIVOT AXIS IN A PLANE NORMAL TO A PLANE DEFINED BY THE PILE FABRIC,FIRST AND SECOND ELECTRICAL SWITCHES MOUNTED ON SAID CARRIAGE, MEANS ONSAID GUIDE ARM FOR SELECTIVELY CLOSING SAID SWITCHES UPON PIVOTALMOVEMENT OF SAID GUIDE ARM IN OPPOSITE DIRECTIONS FROM A NEUTRALPOSITION IN WHICH BOTH OF SAID SWITCHES ARE OPEN, MEANS ELECTRICALLYCONNECTING SAID SWITCHES WITH SAID MOTOR FOR ENERGIZING THE SAME TODRIVE SAID CARRIAGE TOWARD THE PILE FABRIC UPON CLOSING SAID FIRSTSWITCH AND TO DRIVE SAID CARRIAGE AWAY FROM THE PILE FABRIC UPON CLOSINGSAID SECOND SWITCH, A GUIDE FINGER ON SAID GUIDE ARM FOR OVERLYING THESELVAGE IN FRONT OF SAID CUTTER BLADE AND FOR FRICTIONALLY ENGAGING SAIDPILE EDGE AS THE PILE IS MOVED PAST SAID GUIDE FINGER, SAID FRICTIONALENGAGEMENT BETWEEN SAID PILE EDGE AND SAID GUIDE FINGER PRODUCING AFORCE COMPONENT IN THE DIRECTION DEFINED BY THE FABRIC FEED AND ACTINGUPON THE GUIDE FINGER TO BIAS SAID GUIDE ARM PIVOTALLY IN THE DIRECTIONTO CLOSE SAID SECOND SWITCH, AND MEANS FOR PIVOTALLY BIASING SAID GUIDEARM IN THE DIRECTION TO CLOSE SAID FIRST SWITCH, WHEREBY SAID BIASES AREOPPOSED AND, WHEN BALANCED, SAID GUIDE ARM IS DISPOSED IN THE NEUTRALPOSITION AND, WHEN UNBALANCED, SAID GUIDE IS PIVOTALLY MOVED TO CLOSETHE RESPECTIVE ONE OF SAID SWITCHES.